Risk Adapted Spinal Cord/Cauda Constraint Relaxation for High-risk Patients With Metastatic Epidural Spinal Cord Compression Undergoing Spine Stereotactic Radiosurgery

Eligibility Criteria

• 1. Greater than or equal to 18 years old
• 2. Radiographically documented spinal metastasis on spine MRI within 4 weeks of registration
• 3. Proximity of spinal metastasis to spinal cord or cauda equina which precludes achieving a GTV Dmin of at least 14 Gy per the PI
• 4. All participants must be able to receive single fraction SSRS at the site of interest with 0.01 cc of the spinal cord receiving 14-16 Gy and/or 0.01 cc of the cauda equina receiving 18-20 Gy. The goal of treatment is to select the minimal dose to the organ at risk which will achieve a GTV Dmin of 14 Gy at the treating physician's discretion.
• 5. Maximum of 3 contiguous vertebral levels involved with metastasis in the spine to be irradiated in a single session
• 6. All participants must be able to receive a single fraction spine radiosurgery at the designated site of interest to at least a dose of 18 Gy
• 7. All participants must have a vertebral level site of interest from C1 to S2
• 8. Signed informed consent
• 9. Diagnosis of cancer excluding ultra-radiosensitive histologies (see 4.2)
• 10. Motor strength ≥ 4 out of 5 in extremity or extremities affected by the level of cord compression
• 11. ECOG ≤ 2
• 1. Participants with ultra-radiosensitive histologies (lymphoma, multiple myeloma/plasmacytoma)
• 2. Prior history of radiation at the spinal site of interest
• 3. Inability to lie supine comfortably for ≥ 60 minutes
• 4. Progressive neurological deficits due to compression
• 5. Inability of obtain an MRI
• 6. Inability or refusal to undergo an MR simulation
• 7. No eligible for single fraction SSRS for any reason
• 8. Participants who are pregnant